Vitamin K2 (MK-7)
Also known as: menaquinone-7, MK-7, MK7, natto vitamin K2, MenaQ7
Menaquinone-7 is the long-chain vitamin K2 originally isolated from natto and now made by Bacillus fermentation or synthesis. NIH ODS notes it is well absorbed and has a longer half-life than K1, which keeps blood levels steadier at microgram doses. It is the K2 form most often paired with vitamin D3 in bone and cardiovascular formulas, on the strength of 3-year trials at 180 mcg per day in postmenopausal women. All-trans MK-7 is the bioactive isomer, so assay for it rather than total MK-7.
Research summary
Cofactor for gamma-glutamyl carboxylase, activating osteocalcin (bone) and matrix Gla protein (a vascular calcification inhibitor); its long side chain extends circulation time in lipoproteins.
Dosage
Daily amounts, of compound.
| Lowest studied | Typical range | Highest studied | Upper limit |
|---|---|---|---|
| 45 mcg | 90–200 mcg | 375 mcg | — |
Doses are mcg MK-7 (specify all-trans). Adequate Intake for vitamin K is 120 mcg men and 90 mcg women; DV 120 mcg; no UL. Randomized trials used 180 mcg/day for 3 years in healthy postmenopausal women (Knapen 2013, 2015), 200 mcg/day for 12 weeks in type 2 diabetes (Karamzad 2022), and 375 mcg/day for 24 weeks in hemodialysis patients (Naiyarakseree 2023). Fat-soluble; take with a meal, ideally alongside vitamin D3. Some products use 45 mcg as a low-dose multivitamin level.
Standardization: all-trans MK-7 ≥96% of total MK-7; supplied as 0.1% to 2% dilutions
Source material: Bacillus subtilis natto fermentation or synthetic
As supplied: Typically a 1% to 2% powder on a carrier or a 1% oil; 0.1 mg per mcg assumes a 1% grade
Forms of Vitamin K
| Form | Typical dose | Element % | Formats | Price |
|---|---|---|---|---|
| Vitamin K2 (MK-7) | 90–200 mcg | — | Capsule, Softgel, Tablet, Gummy, Liquid, Powder | mid |
| Vitamin K1 (Phylloquinone) | 90–200 mcg | — | Capsule, Tablet, Powder, Softgel, Gummy, Liquid | low |
| Vitamin K2 (MK-4) | 100–1,500 mcg | — | Capsule, Softgel, Tablet, Powder, Liquid | mid |
Format suitability
- Capsule
- Powder
- Tablet
- Softgel
- Gummy
- Liquid
Sensitive to light, alkaline pH, and some mineral premixes (magnesium and calcium oxides); use a protected or microencapsulated grade in mineral-heavy tablets.
Formulation notes
Antagonizes warfarin and similar anticoagulants; needs a label caution. Standard partner for vitamin D3 and calcium. Natto-derived material may carry soy labeling in some supply chains; synthetic grades avoid it.
- Notable drug interactions
Sources
- Vitamin K — Health Professional Fact SheetNIH ODS
- Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women. (Knapen MH, 2013)PubMed
- Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women. A double-blind randomised clinical trial. (Knapen MH, 2015)PubMed
- Effect of Menaquinone-7 Supplementation on Arterial Stiffness in Chronic Hemodialysis Patients: A Multicenter Randomized Controlled Trial. (Naiyarakseree N, 2023)PubMed
Related ingredients
Cod Liver Oil
Fatty acidCod liver oil is pressed from the livers of Atlantic cod.
Typical: 1,000–2,000 mg
Vitamin K1 (Phylloquinone)
VitaminPhylloquinone is the plant form of vitamin K found in leafy greens and the main dietary form.
Typical: 90–200 mcg
Vitamin K2 (MK-4)
VitaminMenaquinone-4 is the short-chain vitamin K2 that the body itself makes from phylloquinone and the form present in meat, eggs, and dairy.
Typical: 100–1,500 mcg
Vitamin D3 (Cholecalciferol)
VitaminThe form of vitamin D the body makes from sunlight and the most effective supplemental form for raising blood levels.
Typical: 1,000–2,000 IU
Fish Oil (EPA/DHA Concentrate)
Fatty acidFish oil concentrate is a refined marine oil enriched in the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Typical: 500–2,000 mg